Subtle play by Carlsen. I'd have played 32.Rd4 and I imagine many would do the same.
29... c5a6  30. b4b5 There was no need to complicate the game, but calling it a mistake is maybe too much. White keeps a clear and stable advantage with 30.a3 or 30.Nc2. 30... c6b5  31. d4b5 White goes after the d6-pawn. 31... a8c8 